Arrest under Massachusetts "idle and disorderly person" statute was unlawful under Massachusetts law, where defendant was arrested for yelling, screaming, swearing and generally causing a disturbance but, though the yelling was undoubtedly loud enough to attract the attention of other guests in hotel, it did not rise to level of "riotous commotion" or "public nuisance." U.S. v. Pasqualino, D.Mass.1991, 768 F.Supp. 13.

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Defendant who did not physically resist his arrest arising out of a domestic violence incident could not be convicted of disorderly conduct based solely on his loud and angry tirade, which included profanities, directed at police officers as he was being escorted to police cruiser, even if spectators gathered to watch defendant; defendant did not make any threats or engage in violence, and his speech did not constitute fighting words. Com. v. Mallahan (2008) 72 Mass.App.Ct. 1103, 889 N.E.2d 77, 2008 WL 2404550.

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Defendant's conduct, namely, flailing his arms and shouting at police, victim of recent assault, or both, after being told to leave area by police, did not amount to "violent or tumultuous behavior" within scope of disorderly conduct statute, absent any claim that defendant's protestations constituted threat of violence, or any evidence that defendant's flailing arms were anything but physical manifestation of his agitation or that noise and commotion caused by defendant's behavior was extreme. Com. v. Lopiano (2004) 805 N.E.2d 522, 60 Mass.App.Ct. 723.

UCLA School of Law Professor Adam Winkler, writing for the Huffington Post, agrees with Posner:

Obama was right the first time.

I don't know if the police officer arrested Gates because of the Harvard professor's race. A lot of white people would say that if they mouthed off to a cop, they too would be arrested.

But one thing is clear: Gates did not violate any law. Under Massachusetts law, which the police officer was supposedly enforcing, yelling at a police officer is not illegal.

The law on the books for disorderly conduct is available online at mass.gov -- but what do you think? Does this change your notion of the case?